The invention relates to a transfer line for the metal-cutting machining of workpieces, in which a plurality of machining stations comprising tools together with their drives and guides are arranged one after the other substantially in one plane and transfer devices convey the workpieces to the machining stations in which the workpieces are held by clamping devices during machining.
Transfer lines of the type described above are known. They serve, for example, for the fully automatic machining of workpieces of essentially the same kind, for example engine blocks. In the individual machining stations of the transfer line, the various machining operations are performed by suitable machining units and tools. When the machining operations are completed, the transfer devices move the workpieces in an operating cycle to the next machining station.
As a rule, liquid cooling lubricants are employed for the machining operations, the function of which is to lubricate and cool the tools and also to flush away the cut-off cuttings. For this purpose, there is arranged beneath the workpiece-conveying path a channel which receives the cuttings and the coolant. The channel may be arranged either in the machine bed or on the floor on which the machining stations also stand, or a suitable underfloor channel or drain is provided. In the channel or drain, there are then provided conveying devices for the cuttings, for example screw conveyors, band conveyors, scraper conveyors, flap conveyors or else flushing nozzles, which carry the cuttings away.
The use of the cooling lubricant is relatively expensive. On the one hand, a high delivery rate is required, and on the other hand appropriate devices for maintaining a supply of and for cleaning the cooling lubricant are required.
An object of the present invention is to avoid the use of cooling lubricant as far as possible, especially as the wetting of the cuttings by the cooling lubricant is also undesirable.